Epitaxial Relationships between Uric Acid Crystals and Mineral Surfaces:  A Factor in Urinary Stone Formation

Langmuir ◽  
2004 ◽  
Vol 20 (16) ◽  
pp. 6524-6529 ◽  
Author(s):  
M. Crina Frincu ◽  
Caitlin E. Fogarty ◽  
Jennifer A. Swift
Keyword(s):  
Uric Acid ◽  
Stone Formation ◽  
Urinary Stone ◽  
Mineral Surfaces

scholarly journals Composition and Morphology of Nanocrystals in Urines of Lithogenic Patients and Healthy Persons

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Bao-Song Gui ◽  
Rong Xie ◽  
Xiu-Qiong Yao ◽  
Mei-Ru Li ◽  
Jian-Ming Ouyang
Keyword(s):  
Uric Acid ◽  
Calcium Oxalate ◽  
Stone Formation ◽  
Calcium Oxalate Monohydrate ◽  
Urinary Stone ◽  
Calcium Oxalate Dihydrate ◽  
Transmission Electron ◽  
Mean Size ◽  
Healthy Persons ◽  
Healthy Urine

The composition and morphology of nanocrystals in urines of healthy persons and lithogenic patients were comparatively investigated by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was shown that the main composition of urinary nanocrystals in healthy persons were calcium oxalate dihydrate (COD), uric acid, and ammonium magnesium phosphate (struvite). However, the main compositions of urinary nanocrystals in lithogenic patients were struvite,β-tricalcium phosphate, uric acid, COD, and calcium oxalate monohydrate (COM). According to the XRD data, the size of nanocrystals was calculated to be23∼72 nm in healthy urine and12∼118 nm in lithogenic urine by Scherer formula. TEM results showed that the nanocrystals in healthy urine were dispersive and uniform with a mean size of about 38 nm. In contrast, the nanocrystals in lithogenic urine were much aggregated with a mean size of about 55 nm. The results in this work indicated that the urinary stone formation may be prevented by diminishing the aggregation and the size differentiation of urinary nanocrystals by physical or chemical methods.

scholarly journals Biochemical urinalysis of healthy kidney and stone-generating kidney in unilateral urolithiasis

2019 ◽  
Vol 8 (2) ◽  
pp. 151-156
Author(s):  
Feramarz Mohammadalibeigi ◽  
Majid Shirani ◽  
Hamed Seyed-Salehi ◽  
Lotfollah Afzali
Keyword(s):  
Uric Acid ◽  
Kidney Stone ◽  
Stone Formation ◽  
Urinary Stone ◽  
Metabolic Factors ◽  
Cross Sectional ◽  
Urinary Sample ◽  
The Mean ◽  
The Difference ◽  
Southwest Iran

Introduction: Oxalate, calcium, uric acid, and citrate are among the most widely known biochemical factors for urinary stone formation. In most cases, urolithiasis occurs as unilateral despite the role of systemic metabolic factors in kidney stone formation. Objectives: The present research aimed to compare these urinary biochemical factors in healthy and stone-generating kidneys in patients with unilateral urolithiasis. Patients and Methods: Forty patients with unilateral urolithiasis participated in this cross-sectional, descriptive-analytical study. The patients were hospitalized in kidney surgery and kidney urology ward of Kashani hospital of Shahrekord, southwest Iran. After the implementation of crushing stone using transurethral lithotripsy (TUL), 5-10 cc of urinary sample was collected from each kidney. An AutoAnalyzer (Mindray Company, Bs–360 model) and laboratory kits (Bionic Company) were used to measure calcium, uric acid, and creatinine. Moreover, a manual method and Darman Faraz Kave company kits were applied to measure the levels of oxalate and citrate. Results on the healthy and stone-generating kidneys of each patient were separately analyzed using the Stata 13 software. Results: The difference in the mean ratio of uric acid, oxalate, and citrate to creatinine in the healthy kidneys and stone-generating kidneys was not significant. However, the mean UCa/UCr ratio in the healthy kidneys was 0.27±0.07 and relatively greater than that in the stone-generating kidneys (0.11±0.04) (P=0.06). Conclusion: The studied topical factors and secretory disorders had not any significant relationship with unilateral urolithiasis. The cause of unilateral urolithiasis should be searched in other factors such as metabolic factors, main positions of individual during 24 hours and sleeping, and anatomic disorders of kidney stone, or multifactorial.

scholarly journals Development of a Portable Multi-Sensor Urine Test and Data Collection Platform for Risk Assessment of Kidney Stone Formation

Electronics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2180
Author(s):  
Wen-Yaw Chung ◽  
Roozbeh Falah Ramezani ◽  
Angelito A. Silverio ◽  
Vincent F. Tsai
Keyword(s):  
Risk Assessment ◽  
Uric Acid ◽  
Data Collection ◽  
Stone Formation ◽  
Urinary Stone ◽  
Measurement Range ◽  
Urine Ph ◽  
System Validation ◽  
Stone Former ◽  
And Gender

In this paper, we present an Internet of things (IoT)-based data collection system for the risk assessment of urinary stone formation, or urolithiasis, by the measurement and storage of four parameters in urine: pH, concentrations of ionized calcium (Ca2+), uric acid and total dissolved solids. The measurements collected by the system from patients and healthy individuals grouped by age and gender will be stored in a cloud database. These will be used in the training phase of an artificial intelligence (AI) machine learning process utilizing the logistics regression model. The trained model provides a binary risk assessment, indicating if the end user is either a stone-former or not. For system validation, standard chemical solutions were used. Preliminary results indicated a sufficient measurement range, falling within the physiological range, and resolution for pH (2.0–10.0, +/−0.1), Ca2+(0.1–3.0 mmol/l, +/−0.05), uric acid (20–500 ppm, +/−1) and conductivity (1.0–40.0 mS/cm, +/−0.1), exhibiting high correlation with standard instruments. We intend to deploy this system in few hospitals in Taiwan to collect the data of patients’ urine, with analysis aided by urologist assessments for the risk of urolithiasis. The modularized design allows future modification and expansion to accommodate other sensing analytes.

scholarly journals Proteus mirabilis Urease: Unsuspected Non-Enzymatic Properties Relevant to Pathogenicity

2021 ◽  
Vol 22 (13) ◽  
pp. 7205
Author(s):  
Matheus V. C. Grahl ◽  
Augusto F. Uberti ◽  
Valquiria Broll ◽  
Paula Bacaicoa-Caruso ◽  
Evelin F. Meirelles ◽  
...  
Keyword(s):  
Proteus Mirabilis ◽  
Stone Formation ◽  
Cell Types ◽  
Bioinformatic Analysis ◽  
Urinary Stone ◽  
Enzymatic Properties ◽  
Hek293 Cells ◽  
Urinary Stones ◽  
Isolated Cells ◽  
Tnf Α

Infection by Proteus mirabilis causes urinary stones and catheter incrustation due to ammonia formed by urease (PMU), one of its virulence factors. Non-enzymatic properties, such as pro-inflammatory and neurotoxic activities, were previously reported for distinct ureases, including that of the gastric pathogen Helicobacter pylori. Here, PMU was assayed on isolated cells to evaluate its non-enzymatic properties. Purified PMU (nanomolar range) was tested in human (platelets, HEK293 and SH-SY5Y) cells, and in murine microglia (BV-2). PMU promoted platelet aggregation. It did not affect cellular viability and no ammonia was detected in the cultures’ supernatants. PMU-treated HEK293 cells acquired a pro-inflammatory phenotype, producing reactive oxygen species (ROS) and cytokines IL-1β and TNF-α. SH-SY5Y cells stimulated with PMU showed high levels of intracellular Ca2+ and ROS production, but unlike BV-2 cells, SH-SY5Y did not synthesize TNF-α and IL-1β. Texas Red-labeled PMU was found in the cytoplasm and in the nucleus of all cell types. Bioinformatic analysis revealed two bipartite nuclear localization sequences in PMU. We have shown that PMU, besides urinary stone formation, can potentially contribute in other ways to pathogenesis. Our data suggest that PMU triggers pro-inflammatory effects and may affect cells beyond the renal system, indicating a possible role in extra-urinary diseases.

scholarly journals Nutrition and Kidney Stone Disease

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1917
Author(s):  
Roswitha Siener
Keyword(s):  
Kidney Stone ◽  
Fluid Intake ◽  
Stone Formation ◽  
Urinary Stone ◽  
Stone Disease ◽  
Urinary Stones ◽  
Dietary Therapy ◽  
Effective Prevention ◽  
Kidney Stone Disease ◽  
Nutrition And Diet

The prevalence of kidney stone disease is increasing worldwide. The recurrence rate of urinary stones is estimated to be up to 50%. Nephrolithiasis is associated with increased risk of chronic and end stage kidney disease. Diet composition is considered to play a crucial role in urinary stone formation. There is strong evidence that an inadequate fluid intake is the major dietary risk factor for urolithiasis. While the benefit of high fluid intake has been confirmed, the effect of different beverages, such as tap water, mineral water, fruit juices, soft drinks, tea and coffee, are debated. Other nutritional factors, including dietary protein, carbohydrates, oxalate, calcium and sodium chloride can also modulate the urinary risk profile and contribute to the risk of kidney stone formation. The assessment of nutritional risk factors is an essential component in the specific dietary therapy of kidney stone patients. An appropriate dietary intervention can contribute to the effective prevention of recurrent stones and reduce the burden of invasive surgical procedures for the treatment of urinary stone disease. This narrative review has intended to provide a comprehensive and updated overview on the role of nutrition and diet in kidney stone disease.

Nephrolithiasis

2018 ◽  
Author(s):  
José Luiz Nishiura ◽  
Ita Pfeferman Heilberg
Keyword(s):  
Uric Acid ◽  
Calcium Oxalate ◽  
Dietary Habits ◽  
Stone Formation ◽  
Urine Volume ◽  
First Episode ◽  
Dietary Advice ◽  
Dietary Recommendations ◽  
Genetic Traits ◽  
Oxalate Precipitation

Nephrolithiasis is a highly prevalent condition, but its incidence varies depending on race, gender, and geographic location. Approximately half of patients form at least one recurrent stone within 10 years of the first episode. Renal stones are usually composed of calcium salts (calcium oxalate monohydrate or dihydrate, calcium phosphate), uric acid, or, less frequently, cystine and struvite (magnesium, ammonium, and phosphate). Calcium oxalate stones, the most commonly encountered ones, may result from urinary calcium oxalate precipitation on the Randall plaque, which is a hydroxyapatite deposit in the interstitium of the kidney medulla. Uric acid nephrolithiasis, which is common among patients with metabolic syndrome or diabetes mellitus, is caused by an excessively acidic urinary pH as a renal manifestation of insulin resistance. The medical evaluation of the kidney stone patient must be focused on identifying anatomic abnormalities of the urinary tract, associated systemic diseases, use of lithogenic drugs or supplements, and, mostly, urinary risk factors such as low urine volume, hypercalciuria, hyperuricosuria, hypocitraturia, hyperoxaluria, and abnormalities in urine pH that can be affected by dietary habits, environmental factors, and genetic traits. Metabolic evaluation requires a urinalysis, stone analysis (if available), serum chemistry, and urinary parameters, preferably obtained by two nonconsecutive 24-hour urine collections under a random diet. Targeted medication and dietary advice are effective to reduce the risk of recurrence. Clinical, radiologic, and laboratory follow-ups are needed to prevent stone growth and new stone formation, to assess treatment adherence or effectiveness to dietary recommendations, and to allow adjustment of pharmacologic treatment. This review contains 5 highly rendered figure, 3 tables, and 105 references.

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